Security closure

ABSTRACT

A domestic security closure in a form of a cabinet having a front opening (9) defined at the top of a framework (2) partially embedded in the floor and providing a guide for a pair of rigid steel doors (10,12) which can be lifted by use of a counter-weighted chain drive system (20,21,24,25) from a retracted position below floor level (8) to a raised position in which they are locked in place securely to close the cabinet, for instance using a mortise deadlock (29) and a locking bar (27). The flush floor enables entry of relatively bulky and valuable items without lifting.

This invention relates to a security closure, more particularly a floorstanding security cabinet especially but not exclusively designed forhousing expensive but relatively heavy and bulky items of domesticequipment such as television sets, video recorders, computers and thelike. Small valuables such as jewellery or cameras can readily be storedand locked in a safe for security purposes. However, larger items asmentioned above can not normally be locked away in this manner becausethey are either too large or too heavy to be fitted or lifted into thesafe.

It is known from British Pat. No. 1485076 to provide a safe in an innerstorage case received within an outer protective casing, the inner casebeing retractable from a raised position, in which access can be gainedto its interior, to a lowered position in which it is wholly within theouter protective casing and access thereto is prevented. The innercasing is raised and lowered into and out of the protective outer casingby hydraulic means. The problem with this arrangement is that the wholeof the inner casing has to be raised and lowered so powerful andexpensive hydraulic lifting means are needed to cope with the load.

It is an object of the invention, therefore, to provide a securityclosure in which only the doors thereof are raised and lowered to gainaccess thereto.

According to one aspect of the invention, there is provided a securityclosure comprising a cabint closed by a pair of vertically movable doorsnormally retracted below the level of the floor of the cabinet but whichcan be raised and locked in their raised position.

Preferably the doors are moved by means which simultaneously raise themfrom a lowered position in which they are aligned with each other, onebehind the other, to a raised position in which one door is locatedabove the other to secure the closure.

Conveniently, the invention provides a security closure system whichcomprises of framework for partially embedding in a floor to define acabinet opening at its upper exposed part, a pair of rigid doorsslidable vertically in the framework to close the cabinet when in theirraised position but to be retracted into the floor when the cabinet isopened, and means for locking the doors relative to the frame work intheir raised position in order to lock the cabinet securely closed.

Preferably the invention provides a cabinet having a floor flush withthe external floor (and generally constituted by the same floor) and apair of rigid doors which are fully retractable into the floor to enablelarge items to be admitted to the cabinet, for instance by sliding orwheeling, without having to lift them.

To a greater or lesser extent, the back and sides of the cabinet may bedefined by the physically secure walls of the building but steel sidewalls and a back wall may form part of the cabinet of the invention whenthere are no strong structural walls available.

In a preferred embodiment, one of the vertically movable doors has a lipon it to engage with a corresponding lip on the other door when the twodoors are in their raised position thereby securing the doors fromseparation.

Conveniently the doors are moved by a chain drive system, preferablycounter-weighted, the system including a drive wheel which is exposed tothe exterior of the cabinet to enable manual operation of the chaindrive and thereby the vertically movable doors. The chain drive can beon one side of the closure or both sides if desired.

In a preferred embodiment, the closure includes locking means which maybe in the form of an apertured bar provided at the top of the closureinto which locking elements on the upper door penetrate when said dooris raised, the bar being laterally displacable by the operation of alocking device, such as a mortise dead lock, to obstruct downwardmovement of the locking elements penetrating therethrough. In apreferred arrangement, the doors can be locked in their retractedposition because the locking bar carries a part which engages the oreach counter weight to obstruct movement thereof associated with doorclosing when the lock is operated. Conveniently the locking bar isoperable by the mortise dead lock.

For convenience, the closure preferably includes a pivotted floor flapcovering the floor gap through which the doors pass, this flap beinglifted by the upper edge of the upper door on raising the latter toclose the cabinet.

It is a feature of the preferred cabinet of the invention that the meansfor raising and lowering the doors is operable to reduce the speed oftravel of the upper door as it approaches its fully raised position. Apreferred security closure of the invention will now be described, byway of example only, with reference to the accompanying diagrammaticdrawings, in which:

FIG. 1 is a front view of the arrangement of the basic cabinet structurewith the parts below floor level visible as through the ground beneaththe floor is transparent,

FIG. 2 is a corresponding side view of the arrangement shown in FIG. 1,

FIG. 3 is a scrap view in plan showing the counter weighted chain drivesystem for the doors and

FIG. 4 is a side view of the arrangement shown in FIG. 3, the doorsbeing shown in their raised position.

Referring to FIG. 1, there is shown a framework comprising two uprights2 and a lower cross-member 4 (the upper cross member is not visible).This framework is embedded vertically into the ground or floor structureof a building. The floor level is indicated at 8. The upper part of theframework above floor level defines front opening 9 of a securitycabinet which is closed by a pair or vertically movable doors 10,12. Thelocation where the framework is partially embedded in the floor may bethe entrance to a recess in a house, in which case the walls of therecess will provide the side and back walls of the closure. Otherwise,the framework may form part of a larger framework intergrated with oneor more steel side walls or a steel back wall of the closure. The floorof the cabinet or closure is provided by the floor of the house.Alternatively, it may be the top of a plynth on which the cabinetstands, the doors retracting into the plynth.

A roof 5 is associated with the uprights 2 which, in the illustratedexample, is intergrated with the cabinet side walls 6, it being assumedthat the back wall will be provided by a wall of the house.

The two doors 10, 12 are made of steel and slide vertically between theuprights 2. When the cabinet is open both doors are retracted below thefloor level 8, a pivotted flap (not shown) normally covering the gap inthe floor from which the doors emerge, this flap being lifted by theupper door 12 as it is raised.

The upper steel door 10 has an extension 15 (see FIG. 3) at both sideedges on which guide rollers 13,14 are mounted. The guide rollers 13 runalong the front face and side edge of the generally "H" shaped uprights2 while the rollers 14 run along the reverse face thereof for increasedstability.

The lower steel door 10 also has similar extension plates 16 attached toeach side of it to support guide wheels 17, 18 which also run along theuprights 2. An adjustable stop arrangement 26 (see FIG. 4) is providedon the lower part of one or both extension plates 16

The doors 10,12 are raised and lowered by a counterweighted drive systemshown in more detail in FIGS. 3 and 4. In the illustrated example,Pulleys 20, 21 are provided on one side of the upper part of the cabinetover which respective drive chains 22, 23 pass, one end of each chainbeing connected to a respective door and the other end being connectedto a counter-weight 24, 25. A drive wheel 30 (see FIGS. 1 and 2) isexposed on the outside of the cabinet to enable manual operation of thedoors through its counter-weighted chain drive. The drive wheel 30 isfitted to the same shaft 31 as the pulleys 20, 21. If required,additional pulleys and counter-weights can be attached to the oppositeend of shaft 31. Furthermore, a power drive could be provided instead ofthe manual drive system just described.

The locking means for the doors 10, 12 is show in Figures 3 and 4 andcomprises a laterally movable apertured roof bar 27. Hooked latchingelements 28 are provided on the upper edge of the upper door 12 topenetrate the apertures in the locking bar 27 when the upper door iselevated to its fully raised position. The bar 27 may then be laterallydisplaced by operation of a mortise deadlock 29 to block downwardmovement of the hooked latching elements and thereby lock the doorsecurely closed. The lower edge of the lower door 10 has a flange 36extending from it (see FIG. 3) which engages behind a cross piece (40)extending between the uprights 2 to prevent levering of the doors out ofthe framework.

An extension 32 from the locking bar 27 has an end 33 which terminatesadjacent the counter-weight 25 to the upper door. Thus, if the lock isactuated while both doors are lowered, the end 33 is moved beneathcounterweight 25 to prevent the upper door from being raisedaccidentally.

Referring to FIG. 4, it can be seen that the bottom edge of the upperdoor 12 is provided with an upturned lip 34 which engages with adownturned lip 35 on the top edge of the lower door 10 for addedsecurity when both doors are in their fully raised position.

In operation, the two doors 10, 12 would normally be at rest in theirlowered position along side each other beneath the floor 8. In thisposition, the counterweights 24, 25 would be lifted up higher than theirposition shown in FIG. 4. On turning the drive wheel 30, shaft 31 isrotated with the two drive pullyes 20, 21 keyed to it. As the drivepulley 21 is smaller in diameter than the pulley 20, the chain driven byit moves a lesser distance than the chain driven by the larger pulley20. Furthermore, because the angle of the chain relative to the pulley20 for the upper door increases the higher the door moves, the chainincreasingly exerts less of an upwrad pull on the door so the rate ofclosing of the upper door slows down the nearer it gets to its fullyraised position.

In use, when the doors are opened, i.e. in their fully retractedposition below floor level, valuable bulky items such as television setsor video recorders may be wheeled or otherwise admitted into the cabinetwithout lifting. When the door is closed and locked by operation of themortise deadlock and locking bar, a secured closure is formed to protectthe stored items against theft and possibly if desired against fire. Ifdesired, an alarm system may be incorporated.

The preferred arrangement just described and illustrated in the drawingsmay be modified in various ways within the scope of the invention,especially in respect of the manner in which the doors are guided formovement and the way in which the manual or power-drive is transmittedto the doors. The locking means may also be subjected to modificationbut it is generally preferable to retain a mortise deadlock orequivalent locking device for securing the locking bar or other lockingelement which latches the doors in their raised position in which thecabinet is closed. It will also be apparent that the closure can be madein any size necessary to suit the dimensions and quantity of equipmentwhich it is required to store in a secure manner. As a development ofthe invention, the cabinet can be adapted for use as a vandal proofclosure for use in public places to house, for instance, fireextinguishers. Such a cabinet would have its doors kept in their raisedposition by a solenoid operated bolt, which when released, would allowthe doors to drop quickly into the ground giving access to the fireextinguishers in a matter of seconds. After use, the doors would beraised manually again in the manner already described and locked intheir raised position by means of a solenoid operated bolt. It will beappreciated that if cabinets such as these were used in a sportsstadium, all the bolts would be connected to a central control operatedby a stadium official.

I claim:
 1. A security closure comprising a cabinet closed by a pair ofvertically movable doors, said cabinet having a floor substantiallyflush with an external floor, said cabinet including a frameworkpartially embedded in said external floor to define a cabinet opening,said doors normally retracted below the level of said floor of saidcabinet in said framework one door behind the other, said doors adaptedto be raised in said framework, means for moving said doorssimultaneously raising them from said retracted position to a raisedposition one above the other, said means for moving said doors includingeach door having a chain connected to its upper edge, each said chainpassing over a pulley, each said chain having a counterweight attachedto its free end, each said pulley located near the top of said cabinet,each said pulley near the top of said cabinet located behind and spacedaway from said upper door's raised position, the angle between saidupper edge of said upper door and said pulley increasing as said upperdoor elevates in height, whereby said upper door decelerates as itapproaches its fully raised position, means for locking said closure,said locking means comprising an apertured bar provided at the top ofsaid framework into which locking elements on said upper door penetratewhen said door is raised, said bar being laterally displacable byoperation of a locking device to obstruct downward movement of saidlocking elements penetrating therethrough, said doors being lockable intheir lowered position by a part carried by said apertured bar adaptedto engage a counterweight to obstruct movement thereof associated withdoor closing.
 2. A closure as claimed in 1 wherein said moving meansincludes a drive wheel, a chain drive, said drive wheel connected tosaid chain drive, said drive wheel including a part exposed to allow theexterior of said cabinet adapted to manual operation of said chaindrive.
 3. A closure as claim in claim 1 wherein said apertured bar isoperable by a mortise deadlock.
 4. A closure as claimed in claim 3including a gap in said framework at said external floor, a pivotedfloor flap covering said floor gap through which said doors pass, saidfloor flap adapted to be lifted by the upper edge of said upper door onraising said upper door to close the cabinet.